C 14 dating method
Usually a proton is knocked out of the nitrogen atom's nucleus and is replaced with the neutron.The proton takes an electron with it and becomes an atom of hydrogen.As you might guess, radioactive carbon (C) is quite rare.Only one out of every trillion carbon atoms is C14. The C14 created in the upper atmosphere reacts with oxygen to become carbon dioxide.
Some scientists believe the problem runs far deeper than this, as the following quote shows: In the light of what is known about the radiocarbon method and the way it is used, it is truly astonishing that many authors will cite agreeable determinations as "proof" for their beliefs...When they strike ordinary atoms in the upper atmosphere, the cosmic rays smash them apart. Some of these neutrons then collide with nitrogen atoms.This collision is less destructive than the initial collision that produced them.Radioactive carbon (Carbon 14) is formed in the upper atmosphere as a byproduct of cosmic radiation.Cosmic rays are positively charged atoms moving at enormous speeds.